The various space missions currently planned, such as those of NASA and ESA, envisage taking planet ground samples and returning them to Earth. Some of these missions are already scheduled, such as, for example, the European “Mars Sample Return” program (collection of samples from Mars) planned around 2010.
Numerous studies have been conducted on this subject, and the space agencies have established scenarios according to which samples taken from the ground of planets and packaged in a container for their transportation to Earth were placed in orbit by a launcher from the planet concerned, a probe also placed on this orbit from the Earth being charged with recovering this container to return it to Earth. Such a separation of roles between a launcher placing the container in orbit and a probe charged with capturing it and transporting it to Earth is dictated by the effectiveness of the transfer of masses in orbit (according to the well known laws of orbital mechanics). The result is that the crucial phase of capture in orbit of the samples in their container cannot be avoided. Now, hitherto, no simple system for capturing planet ground samples in orbit has been proposed.
All the known systems are based on the assumption that the sample container is either very heavy and complex (it would then have to include remote control means, thrusters, etc.), or of the passive type. The mechanisms for capturing the probe are therefore very bulky, with unfoldable structures, which requires the probe to perform complex movements. Furthermore, it is generally impossible to simulate on Earth the corresponding process sequences and validate them, because these sequences include long movement procedures performed under zero gravity and involving devices of very large dimensions. The case of a heavy and complex container has been generally eliminated, because no known mission for the next ten years has retained it.